1. Technical Field of the Invention
The present invention relates to a technology for processing an impulse response used to impart reverberation.
2. Description of the Related Art
A technology for changing a time length during which reverberation continues (which will be referred to as a “reverberation time”) in an apparatus for imparting reverberation to a sound signal through convolution of an impulse response has been suggested. For example, Japanese Patent Application Publication No. 2004-294712 describes a technology in which a new impulse response having a desired reverberation time is generated by summing (i.e., linearly combining) two types of impulse responses after multiplying each of the impulse responses by an exponential function.
However, in the technology of Japanese Patent Application Publication No. 2004-294712, the magnitude of noise such as background noise superimposed on the impulse response is also amplified since the magnitude of the impulse response is increased through multiplication by the exponential function. Accordingly, the prior art technology has a problem in that the sound quality of the reverberant sound added to the sound signal is degraded.